Until recently this question would have sounded absurd. Beijing strenuously avoids playing a high-profile part in ameliorating international humanitarian crises. Its most identifiable role in Myanmar had been to shield the local military from international criticism for carrying out what the United Nations high commissioner on human rights has called a “textbook example of ethnic cleansing” that has set off the exodus of more than 600,000 people to neighboring Bangladesh.

As the world has watched the unfolding of a campaign of murder, arson and rape by Myanmar’s military, known as the Tatmadaw, Beijing has blocked attempts by the United Nations Security Council to pass a resolution condemning the attacks, while offering the usual bromides about avoiding “interference” in domestic affairs of other countries.

Then Beijing shifted gears. On Nov. 19, while on a trip to Bangladesh and Myanmar, China’s foreign minister, Wang Yi, announced that Beijing was brokering a “three-phase plan” to bring about “a final and fundamental solution” to the crisis. The “plan,” which was light on details, included a cease-fire, to be followed by the repatriation of refugees from Bangladesh to Myanmar and, later, policies to spur long-term economic development in Rakhine State, home to most of the Rohingya.

Just after Mr. Wang’s visit, on Nov. 23, Bangladesh and Myanmar announced an agreement on the repatriation of refugees. In a clear sign of support of the Chinese role in Myanmar, President Xi Jinping met the country’s powerful army chief, Senior Gen. Min Aung Hlaing, in Beijing, pledging closer military cooperation. And Mr. Xi met with Daw Aung San Suu Kyi, the country’s civilian leader, in Beijing last week.

The unusually high-profile intervention — which appears to be in line with Beijing’s new foreign policy goal of becoming a “leading global power” — is on its face commendable. It’s also understandable given the persistence of ethnic armed conflicts in Myanmar on the Chinese border.

But far from representing a new era in which China upholds victims’ rights and seeks accountability for abuses, China’s intervention is intended to protect its own narrow interests.

China’s actions appear to hold appeal for both Bangladesh and Myanmar. A return of Rohingya refugees would soothe fears in Bangladesh, where a once-welcoming mood has given way to complaints by Bangladeshis about the burden that their poor, densely populated country has been forced to bear. For Myanmar, the rewards are even greater. Even if it is compelled to accept the return of Rohingya refugees, it will be shaded by the protective umbrella of Chinese power from attempts to hold the Tatmadaw accountable for crimes against humanity.

China has stood behind Myanmar as it has thwarted a United Nations fact-finding mission to Rakhine to investigate human rights violations there. It has faithfully echoed Myanmar’s crude official narrative justifying attacks on the Rohingya on the grounds of “fighting terrorism” and preserving “national security.”

For China, tensions between Bangladesh and Myanmar represent a threat to its regional ambitions. Beijing has geopolitical and economic interests in Myanmar, and particularly in Rakhine, where it is developing the port in the city of Kyaukpyu Port and a special economic zone. Mr. Wang reportedly said to Bangladeshi officials last month that Beijing does not want the Rohingya crisis to impede the progress of a Bangladesh-China-India-Myanmar economic initiative.

The Rohingya are a lesser consideration for Beijing. China’s proposal has no guarantee that all of the Rohingya would be allowed to return home, let alone secure recognition or citizenship (most Rohingya are considered “stateless”). Once they crossed back into Myanmar, the Rohingya returnees would be at the mercy of the same Tatmadaw that dispatched them to Bangladesh. The returnees would not be allowed to go to their home villages, which have been reduced to ashes, but consigned to grim internment camps. The system of discrimination and segregation that made them so vulnerable in the first place would become further entrenched with the camps.

Without the international community overseeing the return of Rohingya, the Myanmar authorities can do as they wish. And promoting its own “One Belt, One Road” infrastructure plan as the long-term solution to Myanmar’s crisis in Rakhine, China could displace the comprehensive recommendations made by the Kofi Annan Commission report on the conflict — something that Ms. Aung San Suu Kyi has committed to but that nevertheless remains abhorrent to the Tatmadaw.

Stressing that “reintegration, not segregation, is the best path to long-term stability and development in Rakhine,” the Annan Commission recommended that Myanmar’s authorities carry out a “comprehensive assessment” of how the China-backed Kyaukpyu port and the special economic zone “may affect local communities” and to develop “robust mechanisms” for “consultation with local communities.”

A worrying effect of China’s plan for the Rohingya is that it risks rewarding the crimes committed against them. Myanmar’s ethnic-cleansing generals will be able to retreat deeper into China’s orbit, unburdened by any fears of being held accountable.

Over the past three months, Bangladesh has won a lot of prestige for taking in the Rohingya. But in its desperation to cast off the burden of more than 600,000 refugees, Bangladesh risks squandering that good will. If the Rohingya are abandoned to a fate no less cruel than that which forced them across the border, the government of Prime Minister Sheikh Hasina will be seen as a facilitator of those abuses and could pay the price domestically in next year’s elections.

China has the diplomatic, humanitarian and economic resources to make a real difference in the lives of the Rohingya. But its current maneuvering — which seeks to intervene only to preserve impunity for horrific crimes — is putting them to dangerous use. This is hardly the sort of behavior worthy of a great power that in the words of Mr. Xi, aspires to make “greater contributions to mankind.”

Nicholas Bequelin is the East Asia director for Amnesty International.